For general-purpose type printed circuit boards, a one-sided or double-sided metal clad laminate including a paper fiber base material, an organic fiber base material, or a glass fiber base material is widely employed in numerous fields.
From such metal clad laminate, high planar dimensional stability, and minimal thermal expansion through a heating process in particular, is required for upgrading the connection reliability between the conductor circuit and electronic components formed on the laminate, in addition to excellent punching processability, required when forming a hole for mounting electronic components to be implemented, or when punching a pattern.
Methods for improving the planar dimensional stability of the laminate include employing a material obtained by impregnating a fiber base material with a thermosetting resin composition containing an inorganic filler having a quite small thermal expansion coefficient such as silica, to manufacture the laminate (for example, patent document 1), and employing a special base material such as an alumina-silica fiber cloth, to manufacture the laminate (for example, patent document 2).    [Patent document 1] JP-A No. H06-237055    [Patent document 2] JP-A No. S61-273948